A few months earlier, a different illicit romance had been brewing. To Nath's immense disapproval, all spring Lydia had spent her afternoons out with Jack in his car: driving round and round town, or parking the VW near the green quad of the college, or by the playground, or in a deserted parking lot.

Despite what Nath thought, to Lydia's smug satisfaction, despite the whispers, now and then, when someone glimpsed her climbing into Jack's car -- She's not, is she? No way. Her? Can't be -- despite Lydia's own expectations, the truth was much less scandalous. While the college students scurried to class, or kindergartners scaled the slide, or bowlers trudged into the alley for a quick after-work game, something happened that Lydia had never expected: she and Jack talked. As they sat smoking, feet propped on the dashboard, she told him stories about her parents: how in second grade, she'd traced the diagram of the heart from the encyclopedia, labeling each ventricle with magic marker, and her mother had pinned it up on her bedroom wall as if it were a masterpiece. How at ten, her mother had taught her to take a pulse; how at twelve her mother had persuaded her to skip Cat Malone's birthday party -- the only one she'd ever been invited to -- to finish her science fair project. How her father had insisted she go to the freshman dance and bought her a dress, and she had spent the night standing in the darkest corner of the gym, counting the minutes until she could go home: how late was late enough? Eight thirty? Nine? At first she tried not to mention Nath, remembering how Jack hated him. But she could not talk about herself without Nath and, to her surprise, Jack asked questions: Why did Nath want to be an astronaut? Was he quiet at home like he was at school? So she told him how, after the moon landing, he had bounded across the lawn, pretending to be Neil Armstrong, for days. How, in the sixth grade, he'd convinced the librarian to let him borrow from the adults' section and brought home textbooks on physics, flight mechanics, aerodynamics. How he'd asked for a telescope for his fourteenth birthday and received a clock radio instead; how he'd saved his allowance and bought himself one. How, sometimes, at dinner, Nath never said a word about his day, because their parents never asked. Jack absorbed everything, lighting her next cigarette as she flicked the old butt out the window, tossing her his pack when she ran out. Week after week, she tamped down a flare of guilt at making Nath seem even more pathetic -- because talking about Nath kept her in Jack's car every afternoon, and every afternoon she spent in Jack's car bothered Nath more and more.

"Try again," Jack said. He set his foot on the dashboard and pushed in the cigarette lighter. "Nice and slow. Clutch in, gas out."

"Think of the gas pedal and the clutch as partners," he said. "When one goes up, the other goes down." Under Jack's direction, Lydia let the clutch out slowly and tapped the gas with her toe, and the VW crept forward across the empty parking lot of the roller rink on Route 17. Then the engine stalled, slamming her shoulders into the seat back. Even after a week of practice, the violence of this moment still surprised her, how the whole car jolted and fell silent, as if it had had a heart attack.

Now, in mid-April, Jack had started teaching Lydia to drive. At the end of the month, she would be sixteen.

At the far end of the parking lot, a police car pulled in and executed a neat U-turn, pointing its nose toward the street. They're not looking for us, Lydia told herself. Route 17, out at the edge of town, was a notorious speed trap. Still, the black-and-white car kept catching her eye. She turned the key and restarted the car and stalled again, almost at once.

"Try again," Jack repeated, pulling a pack of Marlboros from his pocket. "You're in too much of a hurry."

She had not realized this, but it was true. Even the two weeks until her birthday, when she could get her learner's permit, seemed eternal. When she had her license, Lydia thought, she could go anywhere. She could drive across town, across Ohio, all the way to California, if she wanted to. Even with Nath gone -- her mind shied from the thought -- she would not be trapped alone with her parents; she could escape anytime she chose. Just thinking about it made her legs twitch, as if itching to run.

Slowly, she thought, taking a deep breath. Just like partners. One goes up, the other goes down. James had promised to teach her to drive their sedan as soon as she had her permit, but Lydia did not want to learn in their car. It was sedate and docile, like a middle-aged mare. It buzzed gently, like a watchful chaperone, if you didn't fasten your seat belt. "After you get your license," her father said, "we'll let you take the car out on Friday nights with your friends."

Lydia sank the clutch to the floor and started the engine again and reached for the gearshift. It was almost five thirty, and her mother would expect her soon. When she tried to let out the clutch, her foot slipped off the pedal. The car bucked and died. The eyes of the policeman in the cruiser flicked toward them, then back toward the road.

"If you keep your grades up," her mother would add, if she was around.

Lydia knew this was a lie, but she nodded. "Yeah," she said hoarsely. "Next time." As they turned onto Route 17, she blew a long column of smoke out toward the police car.

Jack shook his head. "We can try again tomorrow." The coils of the lighter glowed as he pulled it from the socket and pressed a cigarette to its center, the end singeing black against the hot metal, then orange, as if the color had bled. He passed it to Lydia and, once they had switched seats, lit another for himself. "You almost had it," he said, wheeling the car toward the exit of the parking lot.

"So are you going to tell your brother we've been hanging out, and I'm not such a bad guy?" Jack asked when they were nearly home.

She hopped out a block early, and Jack turned the corner and pulled into his driveway while she trotted home, as if she'd walked the whole way herself. Tomorrow, she thought, she would pop the car into first and they would roll across the parking lot, white lines whipping beneath the wheels. On top of the pedals, her feet would feel comfortable, her insteps supple. Soon she would glide down the highway, shifting into third, then fourth, speeding off somewhere all on her own.

Now, Lydia said, "He would never believe me."

Lydia grinned. She suspected that Jack still took other girls out -- some days, he and the VW were nowhere to be found -- but with her, he was practically gentlemanly: he had never even held her hand. So what, if they were only friends? Most days she was the one climbing into his car, and she knew this had not escaped Nath's attention. At dinnertime, while she spun stories for her mother about her grades and her extra credit project, or for her father about Shelley's new perm or Pam's obsession with David Cassidy, Nath watched her -- half-angry, half-afraid -- as if he wanted to say something but didn't know how. She knew what he was thinking, and she let him. Some evenings, she came into Nath's room, plopped down on his windowsill, and lit a smoke, daring him to say something.

It didn't turn out that way. At home, in her room, Lydia flicked on the record player, where the album Hannah had given her for Christmas was already in place -- to Lydia's surprise, she had been playing it over and over. She set the needle an inch and a half from the edge, aiming for the start of her favorite song, but overshot, and Paul Simon's voice suddenly soared into the room: Hey, let your honesty shine, shine, shine --

"Are you done with your homework already?" No answer. Marilyn pursed her lips. "You know, you shouldn't be listening to music if you haven't finished your schoolwork."

"Lydia. Lydia." When her daughter didn't turn around, Marilyn lifted the arm of the record player and the room went quiet, the record spinning helplessly beneath her hand. "That's better. How can you think with that on?"

A faint knocking punched through the music, and Lydia twisted the volume knob as loud as it would go. In a moment, Marilyn, knuckles smarting, opened the door and leaned in.

Lydia picked at a hangnail. "I'll do it after dinner."

"It doesn't bother me."

Oh god, Lydia thought, not again. She blinked fiercely and focused on the corner of her desk, where some article her mother had clipped months ago still sat, furred now with dust.

"Look at me." Marilyn cupped Lydia's chin in her hand and thought of all the things her own mother had never said to her, the things she had longed, her entire life, to hear. "You have your whole life in front of you. You can do anything you want." She paused, looking over Lydia's shoulder at the shelf crammed with books, the stethoscope atop the bookshelf, the neat mosaic of the periodic table. "When I'm dead, that's all I want you to remember."

"Better to get started now, don't you think? Make sure you have time to finish it all and do a careful job?" Marilyn's face softened. "Sweetheart, I know high school may not feel important. But it's the foundation of the rest of your life." She perched on the arm of Lydia's chair and stroked her daughter's hair. It was so crucial to make her understand, but she didn't know how. A quiver had crept into Marilyn's voice, but Lydia didn't notice. "Trust me. Please. Don't let your life slip away from you."

She meant: I love you. I love you. But her words sucked the breath from Lydia's lungs: When I'm dead. All through that long-ago summer, she had thought her mother might really be dead, and those weeks and months had left a persistent, insistent ache in her chest, like a pulsing bruise. She had promised: anything her mother wanted. Anything at all. As long as her mother stayed.

"Enough of that," Marilyn said at last, swatting Lydia playfully on the behind. "Get to work. Supper will be ready in half an hour."

"I know, Mom," she said. "I know." She tugged her notebook from her bookbag. "I'll get started."

All through dinner, the conversation with her mother writhed inside Lydia. She steeled herself with one thought: later, she would tell Nath all about it, and then she would feel better. She excused herself early, leaving half her plate untouched. "I've got to finish my physics," she said, knowing her mother wouldn't protest. Then, on her way upstairs, she passed the hall table, where her father had set the mail just before supper, and one envelope caught her eye: a Harvard seal in the corner, and beneath that, Admissions Office. She slit it open with her finger.

"That's my girl." Marilyn kissed her on the head, right where her hair parted, and Lydia inhaled at last: shampoo, detergent, peppermint. A scent she had known all her life, a scent that, every time she smelled it, she realized she had missed. She curled her arms around Marilyn's waist, pulling her close, so close she could feel her mother's heartbeat against her cheek.

Dear Mr. Lee, she read. We look forward to you joining us on campus April 29-May 2 and have matched you with a host student for your visit. She knew it had been coming, but it had not seemed real until now. The day after her birthday. Without thinking, she ripped the letter and envelope in two. And at that moment, Nath came out of the kitchen.

"Thought I heard you out here," he said. "Can I borrow --" He spotted the red crest on the torn envelope, the letter in pieces in Lydia's hand, and froze.

"Gimme that." Nath snatched the letter. "This is mine. Jesus. What are you doing?"

Lydia flushed. "It's nothing important. I didn't --" But she had crossed a line, and both of them knew it.

"I just --" Lydia could not think of a way to finish.

Nath pieced the ragged edges together, as if he could make the letter whole again. "This is about my visit. What the hell were you thinking? That if I didn't get this, I couldn't go?" Put so starkly, it sounded foolish and pathetic, and tears began to form in the corners of Lydia's eyes, but Nath did not care. It was as if Lydia had been stealing from him. "Get it through your head: I'm going. I'm going that weekend. And I'm going in September." He bolted for the stairs. "Jesus Christ. I can't get out of this house fast enough." In a moment, his door slammed overhead, and although Lydia knew he wouldn't open it -- nor did she know what she would say if he did -- this did not stop her from knocking, again and again and again.

"I know what to do," Lydia said. "I just can't do it." Her hand had cramped into a claw around the gearshift and she pried it away. Partners, she reminded herself. The gas and the clutch were partners. It struck her now: that wasn't true. If one went up, the other had to go down. That was how everything went. Her grade in physics had gone up to a C-minus but her grade in history had slipped to a D. Tomorrow her English essay was due -- two thousand words on Faulkner -- but she could not even find her book. Maybe there was no such thing as partners, she thought. From all her studying, this flashed through her mind: For every action, there is an equal and opposite reaction. One went up and the other went down. One gained, the other lost. One escaped, the other was trapped, forever.

The thought haunted her for days. Although Nath -- cooled down now from the incident of the letter -- was speaking to her again, she could not bear to mention it, even to apologize. Each night after dinner, despite her mother's most pointed nagging, she stayed in her room alone instead of tiptoeing down the hall in search of sympathy. The night before her birthday, James rapped at her door.

The next afternoon, in Jack's car, she stalled the engine over and over until Jack said they'd better call it a day.

Lydia flipped the locket open and froze. Inside were two pictures the size of her thumbnail: one of her father, one of her -- dolled up for the ninth-grade dance the year before. All the way home, she had told him what a wonderful time she'd had. The photo of her father smiled broadly, fondly, expectantly. The photo of herself looked away, serious, resentful, sullen.

"You've seemed down the past couple of weeks," he said. He held out a little blue velvet box the size of a deck of cards. "I thought an early present might cheer you up." It had taken him some time, this gift, and he was proud of it. He had gone so far as to ask Louisa for advice on what a teenage girl might like, and this time, he was sure Lydia would love it.

Inside the box lay a silver heart on a chain. "It's beautiful," Lydia said, surprised. At last, a present that was a present -- not a book, not a hint -- something she wanted, not something they wanted for her. This was the necklace she had longed for at Christmas. The chain slid through her fingers like a stream of water, so lithe it felt almost alive.

James touched her dimple with a fingertip and twisted it, an old joke of his. "It opens."

He fiddled with the clasp of the necklace, struggling with the tiny spring loop. "I wanted gold, but a reliable source told me everyone was wearing silver this year," he said. Lydia ran a finger along the velvet lining of the box. Her father was so concerned with what everyone was doing: I'm so glad you're going to the dance, honey -- everyone goes to the dance. Your hair looks so pretty that way, Lyddie -- everyone has long hair these days, right? Anytime she smiled: You should smile more -- everyone likes a girl who smiles. As if a dress and long hair and a smile could hide everything about her that was different. If her mother let her go out like the other girls, she thought, it might not matter what she looked like -- Jackie Harper had one blue eye and one green, and she'd been voted Most Social last year. Or if she looked like everyone else, perhaps it would not matter that she had to study all the time, that she could not go out on the weekends until she'd done all her homework, that she could not go out with boys at all. One or the other might be overcome. To be pulled both ways -- no dress, no book, no locket could help that.

"I know this year has been tough, and your mother's been asking a lot of you," James said. "Just remember, school isn't everything. It's not as important as friendship, or love." Already he could see a faint line worrying a crease between Lydia's brows, dark circles blooming beneath her eyes from late-night studying. He wanted to smooth that wrinkle with his thumb, to wipe the shadows away like dust. "Every time you look at this, just remember what really matters. Every time you look at this, I want you to smile. Promise?"

"It's beautiful," she whispered, and James mistook her hoarseness for deep gratitude.

"There we go," James said, the catch springing open at last. He refastened it at her nape, and the metal cut a line of cold, like a ring of ice, around her throat. "What do you think? Do you like it?" Lydia understood: this was meant to remind her of all he wanted for her. Like a string tied around her finger, only this lay around her neck.

The next day, in honor of her birthday, she wore the necklace, as her father suggested. "Right after school," James told her, "I'll take you over to get your permit and we'll have our first driving lesson before dinner." Her mother said, "And after dinner, we'll have cake. And I've got some special presents for the birthday girl." Which meant books, Lydia thought. That night Nath would pack his suitcase. All day she consoled herself: In six hours, I will have my permit. In two weeks, I will be able to drive away.

"Promise me," he said, "that you'll get along with everyone. You can never have too many friends." And Lydia closed her eyes and nodded.

James paused the car to let a cluster of junior boys meander across the street. "Louisa has an appointment and since I was coming this way anyway, I offered her a ride."

At three o'clock, her father pulled up in front of the school, but when Lydia picked up her bookbag and started for the sedan, she was surprised to see someone already in the passenger seat: a Chinese woman -- a girl, really -- with long black hair.

"I shouldn't have said yes," Louisa said. "I should have just canceled it. I hate the dentist."

"So nice to finally meet you," the girl said as Lydia climbed into the backseat. "I'm Louisa, your dad's teaching assistant."

As he crossed in front of the car, one of the juniors grinned at them through the windshield and pulled his eyes into slits with his fingers. The others laughed, and Lydia scrunched down in her seat. It occurred to her: the boys probably thought Louisa was her mother. Squirming, she wondered if her father was embarrassed, too, but in the front seat, James and Louisa hadn't noticed a thing.

"Five," Louisa said. "I'm just a poor grad student, not a rich professor." She patted his arm playfully, and the tenderness in her face shocked Lydia. Her mother looked at her father this way, late at night, when he was caught up in his reading and she leaned against his armchair affectionately, before nudging him to bed. Louisa's hand lingered on her father's arm and Lydia stared at them, her father and this girl, cozy in the front seat like a little married couple, a tableau framed by the bright screen of the windshield, and she thought suddenly: This girl is sleeping with my father.

"Ten bucks says you don't even have one cavity," James said.

It had never occurred to her before to think of her father as a man with desires. Like all teenagers, she preferred -- despite her very existence -- to imagine her parents as eternally chaste. But there was something in the way her father and Louisa touched, in their easy banter, that shocked her innocent sensibilities. To her, the faint crackle between them blazed so hotly that her cheeks flushed. They were lovers. She was sure of it. Louisa's hand was still on her father's arm and her father didn't move, as if the caress were nothing unusual. In fact, James did not even notice: Marilyn often rested her hand on him just this way, and the feeling was too familiar to stand out. For Lydia, however, the way her father kept looking straight ahead, eyes still scanning the road, was all the confirmation she needed.

Louisa blinked. "I had some ideas. I mean, I've heard so much about you from your dad."

"Come on, Lyddie," James said, "you've heard me talk about Louisa. How smart she is. How she never lets those undergrads get away with anything." He smiled at Louisa, and Lydia's vision blurred.

"So I hear it's your birthday today," Louisa said, twisting toward the backseat again. "Sixteen. I'm sure this will be a very special year for you." Lydia didn't respond, and Louisa tried again. "Do you like your necklace? I helped pick it out. Your dad asked my advice on what you might like."

"Daddy, where did you drive after you got your license?" she asked suddenly.

Lydia looked her directly in the eye. "Really," she said. "Daddy's never mentioned you."

Lydia hooked two fingers beneath the chain, fighting the urge to yank it from her neck. "How would you know what I like? You don't even know me."

In the rearview mirror, James's eyes flicked open in surprise. "To school, to swim practices and meets," he said. "And on errands, sometimes."

"But not on dates."

"No," James said. His voice cracked briefly, like a teenage boy's. "No, not on dates."

Lydia felt small and sharp and mean, like a tack. "Because you didn't date. Right?" Silence. "Why not? Didn't anybody want to go out with you?"

"Oh, now," Louisa said. "I don't believe that for a minute." She put her arm on James's elbow again, and this time she kept it there until they reached the dentist's office, until James stopped the car and said, to Lydia's outrage, "See you tomorrow."

This time James kept his eyes on the road before them, and his hands on the wheel stiffened, elbows locking.

Despite his daughter glowering in the backseat, James did not realize anything was wrong. At the DMV, he kissed her on the cheek and took a chair. "You'll do fine," he said. "I'll be right here when you're done." Thinking about how excited Lydia would be, permit in hand, he had forgotten all about the moment in the car. Lydia herself, still roiling with the secret she was sure she had discovered, turned away without a word.

At that moment Lydia realized the room had gone silent. Everyone's head was bent over the test. She looked up at the clock, but it told her nothing: not when they started, not when the test ended, only the time, three forty-one. The second hand tick-tick-ticked around from eleven to twelve and the minute hand, like a long iron needle, jumped forward another notch. Three forty-two. She flipped her booklet open. What color is a stop sign? She filled in the circle for B: Red. What must you do if you see or hear an emergency vehicle coming from any direction? In her haste, the pencil slipped outside the bubble in a jagged claw. A few rows up, a girl with pigtails rose, and the woman at the front gestured her into the next room. A moment later, the boy sitting next to her did the same. Lydia looked down at her booklet again. Twenty questions. Eighteen left to go.

In the test room, a woman handed her an exam booklet and a pencil and told her to take any empty seat. Lydia made her way toward the back corner of the room, stepping over bookbags and purses and the legs of the boy in the next-to-last row. Everything her father had ever said to her bounced back in a new tone: You can never have too many friends. She thought of her mother, sitting at home, doing the laundry, filling in a crossword, while her father -- She was furious with him, furious with her mother for letting this happen. Furious with everyone.

Lydia kept her head bent over the desk, as if the words would not be true until she saw the woman's face. A dark spot formed in the middle of the paper, and it took her a moment to realize it was the mark of a tear, that it was hers. She wiped the paper clean with her hand, then wiped her cheek. Everyone else had gone.

If your car begins to skid, you should… All of the answers seemed plausible. She skipped ahead. When are roads and highways most slippery? How much distance should you leave between yourself and the vehicle in front of you under good road conditions? To her right, a man with a mustache closed his booklet and put down his pencil. C, Lydia guessed. A. D. On the next page, she found a list of sentences she could not complete. When driving behind a large truck on the freeway, you should… To safely navigate a curve, you should… When backing up, you should… She repeated each question to herself and got stuck on the last words, like a scratched record: you should, you should, you should. Then someone touched her shoulder, softly, and the woman from the front of the room said, "I'm sorry, dear, time's up."

In the next room, where a man fed answer sheets into the scoring machine, she jabbed her finger with the tip of her pencil. "Eighteen right," the man said to the girl in front of her. "Take this to the counter and they'll take your picture and print your permit. Congratulations." The girl gave a happy little skip as she passed through the door and Lydia wanted to slap her. There was a brief moment of silence as the man looked at Lydia's form, and she focused on the splotch of mud on his boot.

"Well," he said. "Don't feel bad. Lots of people fail the first time." He turned the paper faceup and again she saw the five dark circles, like moles, the rest of the sheet blank and bare. Lydia did not wait for her score. As the machine sucked in the answer sheet, she walked straight past him, back into the waiting room.

There was a long line at the counter for photos now; the man with the mustache counted the bills in his wallet, the girl who had skipped picked at her nail polish. The pigtailed girl and the boy had already gone. On the bench, James sat waiting. "So," he said, looking down at her empty hands. "Where is it?"

"It's okay," the woman said. "You only need fourteen right." But Lydia knew she had filled in only five circles.

"It's okay, honey," he said. "You can try again this weekend." In the cloud of disappointment and humiliation, Lydia did not remember, or care, that she could take the test again. In the morning, Nath would leave for Boston. All she could think was: I will be here forever. I will never be able to get away.

"Can we go home now?" she said.

"I failed," she said. The two women beside her father on the bench looked up at her, then quickly away. Her father blinked, once, twice, as if he hadn't heard her properly.

James put his arm around his daughter, but it weighed on her shoulders like a lead blanket, and she shrugged it off.

"As soon as Lydia comes in," Marilyn said, "we'll say surprise. And then we'll have dinner, and presents after." Nath was up in his room, packing for his trip, and alone with her youngest, she was planning aloud, half talking to herself. Hannah, delighted to have her mother's attention even by default, nodded sagely. Under her breath she practiced -- Surprise! Surprise! -- and watched her mother pipe Lydia's name in blue onto the sheet cake. It was supposed to look like a driver's license, a white-frosted rectangle with a photo of Lydia in the corner where the real photograph would be. Inside, it was chocolate cake. Because this was an extra-special birthday, Marilyn had baked this cake herself -- from a box, true, but she had mixed it, one hand moving the mixer through the cake batter, the other holding the battered aluminum bowl still against the whirling blades. She had let Hannah pick out the tub of frosting, and now she squeezed out the last of the tube of decorator's icing spelling L-Y-D and reached into the grocery bag for another.

Such a special cake, Hannah thought, would taste extra-special, too. Better than just plain vanilla or chocolate. The box had shown a smiling woman hovering over a slice of cake and the words You mix in the love. Love, Hannah decided, would be sweet, like her mother's perfume, and soft as marshmallows. Quietly she extended a finger, gouging a small dip in the perfectly smooth surface of the cake. "Hannah!" Marilyn snapped, and swatted her hand away.

While her mother smoothed the dent with the spatula, Hannah touched the frosting on her finger to her tongue. It was so sweet her eyes watered, and when Marilyn wasn't looking, she wiped the rest of it onto the backside of the tablecloth. She could tell by the little line between her mother's eyebrows that she was still upset, and she wanted to lean her head against Marilyn's aproned thigh. Then her mother would understand that she hadn't meant to mess up the cake. But as she reached out, Marilyn set down the tube of icing mid-letter and lifted her head, listening. "That can't be them already."

By the time Hannah and Nath arrived downstairs, though, Lydia and their father had already come from the garage into the hallway, and the moment for Surprise had passed. Instead Marilyn took Lydia's face between her hands and kissed her on the cheek, hard, leaving a red smudge of lipstick, like a welt.

"You're home early," she said. "Happy birthday. And congratulations." She held out a palm. "So? Let's see it."

Beneath her feet, Hannah felt the floor shiver as the garage door groaned open. "I'll get Nath."

"I failed," Lydia said. She glared from Nath to their mother, as if daring them to be upset.

Marilyn stared. "What do you mean, you failed?" she said, honest surprise in her voice, as if she had never heard the word.

Lydia said it again, louder: "I failed." It was almost, Hannah thought, as if she were mad at their mother, mad at all of them. It could not be just the test. Her face was stony and still, but Hannah saw the tiny trembles -- in her hunched shoulders, in her jaw clenched tight. As if she might shiver to pieces. She wanted to wrap her arms tight around her sister's body, to hold her together, but she knew Lydia would only push her away. No one else noticed. Nath and Marilyn and James glanced at each other, unsure what to say.

On any other day, this would have made Lydia boil over inside. Today -- after the necklace, after the boys in front of the car, after the test, after Louisa -- there was no room left in her for anger. Something within her tipped and cracked.

"Well," Marilyn said at last. "You'll just study the traffic rules and try again when you're ready. It's not the end of the world." She tucked a stray lock of hair behind Lydia's ear. "It's okay. It's not like you failed a school subject, right?"

"Sure, Mom," she said. She looked up at her mother, around at her whole family, and smiled, and Hannah nearly ducked behind Nath. The smile was too wide, too bright, cheery and white-toothed and fake. On her sister's face it was terrifying; it made Lydia look like a different person, a stranger. Again no one else noticed. Nath's shoulders unhunched; James let out his breath; Marilyn wiped her hands, which had grown damp, on her apron.

"Dinner's not quite ready yet," she said. "Why don't you go up and take a shower and relax? We'll eat early, as soon as it's done."

Upstairs, in her room, Lydia yanked at the necklace, which wouldn't break. She unhooked it and slammed it inside its box, as if it were a wild thing, and pushed it deep beneath the bed. If her father asked where it was, she would say she was saving it for special occasions. She would say she didn't want to lose it, don't worry, she'd wear it next time, Daddy. In the mirror, a fine red line ringed her neck.

"What happened?" Marilyn murmured to James, who shook his head. Hannah knew. Lydia hadn't studied. Two weeks ago, before Lydia had come home after school, Hannah had explored her room, looking for treasures. She'd pocketed Lydia's book from the floor of the closet and, beneath it, had found the rules and regulations pamphlet. When Lydia started to study, Hannah had thought, she would notice her book was missing. She would come looking for it. Every few days, she had checked, but the pamphlet hadn't moved. Yesterday it had been half-covered by a pair of beige platforms and Lydia's best bell-bottoms. And the book was still tucked upstairs under Hannah's pillow.

"Great," Lydia said, and this time Hannah actually did turn her face away until she heard her sister's footsteps on the stairs.

By the time Lydia came down to dinner an hour later, the mark had faded away, though the feeling that accompanied it had not. She had dressed up as if for a party, her hair ironed dry and straight and glossy on the big ironing board, her lips coated with jam-colored gloss. James, looking at her, had a sudden memory of Marilyn when they'd first met. "Don't you look nice," he said, and Lydia forced herself to smile. She sat bolt upright with that same fake smile at the dinner table, like a doll on display, but only Hannah spotted its fakeness. Her back ached, watching Lydia, every bit of her did, and she slouched in her own chair until she nearly slid off the seat. As soon as dinner was over, Lydia patted her mouth with her napkin and stood up.

"Wait," Marilyn said. "There's cake." She went into the kitchen and in a moment emerged bearing the cake on a tray, candles aglow. The photo of Lydia was gone, the top of the cake refrosted to plain white, with just Lydia's name. Hiding under the smooth white, Hannah thought, was the pretend driver's license, the Congratulations and the blue L-Y-D. Though you couldn't see it, it was there just underneath, covered up but smudged and unreadable and horrible. And you'd be able to taste it, too. Their father snapped picture after picture, but Hannah didn't smile. Unlike Lydia, she had not yet learned to pretend. Instead she half shut her eyes, like she did during the scary parts of TV shows, so that she could only half see what came next.

Which was this: Lydia waited for them to finish singing. As they reached the last line of the song, James held up the camera and she bent over the cake, lips pursed as if to kiss. Her perfectly made-up face smiled around the table, sweeping each of them in turn. Their mother. Their father. Nath. Hannah did not know everything Lydia thought she understood -- the necklace, Louisa, all I want you to remember -- but she knew that something had shifted inside her sister, that she was balanced on a dangerous, high-up ledge. She sat very still, as if one wrong move might tip Lydia off the edge, and Lydia blew out the flames with one quick puff.